neuron-request@HPLMS2.HPL.HP.COM ("Neuron-Digest Moderator Peter Marvit") (02/21/91)
Neuron Digest Wednesday, 20 Feb 1991 Volume 7 : Issue 10 Today's Topics: Speech Recognition & NNs preprints/reprints available Adaptive Range Coding - Tech Report Available TR available: Yet another ANN/HMM hybrid. header for TR on ANN/HMM hybrid in neuroprose Tech Report Available in Neuroprose New TR Available Manuscript available on BackPercolation AI*IA Call for papers Send submissions, questions, address maintenance and requests for old issues to "neuron-request@hplabs.hp.com" or "{any backbone,uunet}!hplabs!neuron-request" Use "ftp" to get old issues from hplpm.hpl.hp.com (15.255.176.205). ------------------------------------------------------------ Subject: Speech Recognition & NNs preprints/reprints available From: Vince Weatherill <vincew@cse.ogi.edu> Date: Wed, 13 Feb 91 15:30:36 -0800 Reprints and preprints are now available for the following publications of the OGI Speech Group. Please respond directly to me by e-mail or surface mail. Don't forget to include your address with your request. Unless you indicate otherwise, I will send all 6 reports. Vince Weatherill Dept. of Computer Science and Engineering Oregon Graduate Institute 19600 NW von Neumann Drive Beaverton, OR 97006-1999 Barnard, E., Cole, R.A., Vea, M.P., and Alleva, F. "Pitch detection with a neural-net classifier," IEEE Transactions on Acoustics, Speech & Signal Processing, (February, 1991). Cole, R.A., M. Fanty, M. Gopalakrishnan, and R.D.T. Janssen, "Speaker-independent name retrieval from spellings using a database of 50,000 names," Proceedings of the IEEE Interna- tional Conference on Acoustics, Speech and Signal Process- ing, Toronto, Canada, May 14-17, (1991). Muthusamy, Y. K., R.A. Cole, and M. Gopalakrishnan, "A segment- based approach to automatic language identification," Proceedings of the 1991 IEEE International Conference on Acoustics, Speech and Signal Processing, Toronto, Canada, May 14-17, (1991). Fanty, M., R. A. Cole, and , "Spoken Letter Recognition," Proceedings of the Neural Information Processing Systems Conference, Denver, CO, (Nov. 1990). Janssen, R.D.T, M. Fanty, and R.A. Cole, "Speaker-independent phonetic classification in continuous English letters," Proceedings of the International Joint Conference on Neural Networks, Seattle, WA, Jul 8-12, (1991), submitted for publication. Fanty, M., R. A. Cole, and , "Speaker-independent English alpha- bet recognition: Experiments with the E-Set," Proceedings of the 1990 International Conference on Spoken Language Pro- cessing, Kobe, Japan, (Nov. 1990). **************************************************************** PITCH DETECTION WITH A NEURAL-NET CLASSIFIER Etienne Barnard, Ronald Cole, M. P. Vea and Fil Alleva ABSTRACT Pitch detection based on neural-net classifiers is investigated. To this end, the extent of generalization attainable with neural nets is first examined, and it is shown that a suitable choice of features is required to utilize this property. Specifically, invariant features should be used whenever possible. For pitch detection, two feature sets, one based on waveform samples and the other based on properties of waveform peaks, are introduced. Experiments with neural classifiers demonstrate that the latter feature set --which has better invariance properties--performs more successfully. It is found that the best neural-net pitch tracker approaches the level of agreement of human labelers on the same data set, and performs competitively in comparison to a sophisticated feature-based tracker. An analysis of the errors committed by the neural net (relative to the hand labels used for training) reveals that they are mostly due to inconsistent hand labeling of ambiguous waveform peaks. ************************************************************* SPEAKER-INDEPENDENT NAME RETRIEVAL FROM SPELLINGS USING A DATABASE OF 50,000 NAMES Ronald Cole, Mark Fanty, Murali Gopalakrishnan, Rik Janssen ABSTRACT We describe a system that recognizes names spelled with pauses between letters using high quality speech. The sys- tem uses neural network classifiers to locate and classify letters, then searches a database of names to find the best match to the letter scores. The directory name retrieval system was evaluated on 1020 names provided by 34 speakers who were not used to train the system. Using a database of 50,000 names, 972, or 95.3%, were correctly identified as the first choice. Of the remaining 48 names, all but 10 were in the top 3 choices. Ninty nine percent of letters were correctly located, although speakers failed to pause completely about 10% of the time. Classification of indivi- dual spoken letters that were correctly located was 93%. ************************************************************* A SEGMENT-BASED APPROACH TO AUTOMATIC LANGUAGE IDENTIFICATION Yeshwant K. Muthusamy, Ronald A. Cole and Murali Gopalakrishnan ABSTRACT A segment-based approach to automatic language identifica- tion is based on the idea that the acoustic structure of languages can be estimated by segmenting speech into broad phonetic categories. Automatic language identification can then be achieved by computing features that describe the phonetic and prosodic characteristics of the language, and using these feature measurements to train a classifier to distinguish between languages. As a first step in this approach, we have built a multi-language, neural network- based segmentation and broad classification algorithm using seven broad phonetic categories. The algorithm was trained and tested on separate sets of speakers of American English, Japanese, Mandarin Chinese and Tamil. It currently performs with an accuracy of 82.3% on the utterances of the test set. ************************************************************* SPOKEN LETTER RECOGNITION Mark Fanty and Ron Cole ABSTRACT Through the use of neural network classifiers and careful feature selection, we have achieved high-accuracy speaker- independent spoken letter recognition. For isolated letters, a broad-category segmentation is performed Location of segment boundaries allows us to measure features at ------------------------------ Subject: Adaptive Range Coding - Tech Report Available From: Bruce E Rosen <rosen@CS.UCLA.EDU> Date: Thu, 14 Feb 91 11:11:46 -0800 REPORT AVAILABLE ON ADAPTIVE RANGE CODING At the request of a few people at NIPS, I placed in the connectionists archive the postscript version of my report describing adaptive range coding. Below are the abstract and instructions on ftp retrieval. I would very much welcome any discussion of this subject. If you want, send email to me and I can summarize later for the net. Thanks Bruce --------------------------------------------------------------------------- Report DMI-90-4, UCLA Distributed Machine Intelligence Laboratory, January 1991 Adaptive Range Coding Abstract This paper examines a class of neuron based learning systems for dynamic control that rely on adaptive range coding of sensor inputs. Sensors are assumed to provide binary coded range vectors that coarsely describe the system state. These vectors are input to neuron-like processing elements. Output decisions generated by these "neurons" in turn affect the system state, subsequently producing new inputs. Reinforcement signals from the environment are received at various intervals and evaluated. The neural weights as well as the range boundaries determining the output decisions are then altered with the goal of maximizing future reinforcement from the environment. Preliminary experiments show the promise of adapting "neural receptive fields" when learning dynamical control. The observed performance with this method exceeds that of earlier approaches. ----------------------------------------------------------------------- To obtain copies of the postscript file, please use Jordan Pollack's service: Example: unix> ftp cheops.cis.ohio-state.edu # (or ftp 128.146.8.62) Name (cheops.cis.ohio-state.edu:): anonymous Password (cheops.cis.ohio-state.edu:anonymous): <ret> ftp> cd pub/neuroprose ftp> binary ftp> get (remote-file) rosen.adaptrange.ps.Z (local-file) rosen.adaptrange.ps.Z ftp> quit unix> uncompress rosen.adaptrange.ps unix> lpr -P(your_local_postscript_printer) rosen.adaptrange.ps ---------------------------------------------------------------------------- If you have any difficulties with the above, please send e-mail to rosen@cs.ucla.edu. DO NOT "reply" to this message, please. ------------------------------ Subject: TR available: Yet another ANN/HMM hybrid. From: Yoshua BENGIO <yoshua@homer.cs.mcgill.ca> Date: Sun, 17 Feb 91 21:20:42 -0500 The following technical report is now available by ftp from neuroprose: Yoshua Bengio, Renato De Mori, Giovanni Flammia, and Ralf Kompe (1990), "Global Optimization of a Neural Network - Hidden Markov Model Hybrid", Technical Report TR-SOCS-90.22, December 1990, School of Computer Science, McGill University. Abstract: Global Optimization of a Neural Network - Hidden Markov Model Hybrid Yoshua Bengio, Renato De Mori, Giovanni Flammia, Ralf Kompe TR-SOCS-90.22, December 1990 In this paper a method for integrating Artificial Neural Networks (ANN) with Hidden Markov Models (HMM) is proposed and evaluated. ANNs are suitable to perform phonetic classification, whereas HMMs have been proven successful at modeling the temporal structure of the speech signal. In the approach described here, the ANN outputs constitute the sequence of observation vectors for the HMM. An algorithm is proposed for global optimization of all the parameters. An incremental design method is described in which specialized networks are integrated to the recognition system in order to improve its performance. Results on speaker-independent recognition experiments using this integrated ANN-HMM system on the TIMIT continuous speech database are reported. --------------------------------------------------------------------------- Copies of the postscript file bengio.hybrid.ps.Z may be obtained from the pub/neuroprose directory in cheops.cis.ohio-state.edu. Either use the Getps script or do this: unix-1> ftp cheops.cis.ohio-state.edu # (or ftp 128.146.8.62) Connected to cheops.cis.ohio-state.edu. Name (cheops.cis.ohio-state.edu:): anonymous 331 Guest login ok, sent ident as password. Password: neuron 230 Guest login ok, access restrictions apply. ftp> cd pub/neuroprose ftp> binary ftp> get bengio.hybrid.ps.Z ftp> quit unix-2> uncompress bengio.hybrid.ps.Z unix-3> lpr -P(your_local_postscript_printer) bengio.hybrid.ps Or, order a hardcopy by sending your physical mail address to yoshua@cs.mcgill.ca, mentioning Technical Report TR-SOCS-90.22. PLEASE do this only if you cannot use the ftp method described above. ------------------------------ Subject: header for TR on ANN/HMM hybrid in neuroprose From: Yoshua BENGIO <yoshua@homer.cs.mcgill.ca> Date: Tue, 19 Feb 91 14:33:08 -0500 The following technical report available by ftp from neuroprose was recently advertised: Yoshua Bengio, Renato De Mori, Giovanni Flammia, and Ralf Kompe (1990), "Global Optimization of a Neural Network - Hidden Markov Model Hybrid", Technical Report TR-SOCS-90.22, December 1990, School of Computer Science, McGill University. However, it was not mentionned that the front pages of the TR are in bengio.hybrid_header.ps.Z whereas the paper itself is in: bengio.hybrid.ps.Z Sorry for the inconvenience, Yoshua Bengio School of Computer Science, McGill University ------------------------------ Subject: Tech Report Available in Neuroprose From: Mark Plutowski <pluto@cs.UCSD.EDU> Date: Tue, 19 Feb 91 12:21:17 -0800 [[ Editor's Note: Readers, if you want a copy of this paper mailed to you, BE SURE to include the US$5.00 in your request. It costs real money to make photocopies and send papers by surface mail -- especially overseas. -PM ]] The following report has been placed in the neuroprose archives at Ohio State University: UCSD CSE Technical Report No. CS91-180 Active selection of training examples for network learning in noiseless environments. Mark Plutowski Department of Computer Science and Engineering, UCSD, and Halbert White Institute for Neural Computation and Department of Economics, UCSD. Abstract: We derive a method for {\sl actively selecting} examples to be used in estimating an unknown mapping with a multilayer feedforward network architecture. Active selection chooses from among a set of available examples an example which, when added to the previous set of training examples and learned, maximizes the decrement of network error over the input space. New examples are chosen according to network performance on previous training examples. In practice, this amounts to incrementally growing the training set as necessary to achieve the desired level of accuracy. The objective is to minimize the data requirement of learning. Towards this end, we choose a general criterion for selecting training examples that works well in conjunction with the criterion used for learning, here, least squares. Examples are chosen to minimize Integrated Mean Square Error (IMSE). IMSE embodies the effects of bias (misspecification of the network model) and variance (samplingvariation due to noise). We consider a special case of IMSE, Integrated Squared Bias, (ISB) to derive a selection criterion ($\Delta ISB$) which we maximize to select new training examples. $\Delta ISB$ is applicable whenever sampling variation due to noise can be ignored. We conclude with graphical illustrations of the method, and demonstrate its use during network training. =-=-=-=-=-=-=-=-=-=-=-=-= How to obtain a copy -=-=-=-=-=-=-=-=-=-=-=-=-=-= Copies may be obtained by a) FTP directly from the Neuroprose directory, or b) by land mail from the CSE dept. at UCSE. a) via FTP: To obtain a copy from Neuroprose, either use the "getps" program, or ftp the file as follows: % ftp cheops.cis.ohio-state.edu Connected to cheops.cis.ohio-state.edu. 220 cheops.cis.ohio-state.edu FTP server (Version 5.49 Tue May 9 14:01:04 EDT 1989) ready. Name (cheops.cis.ohio-state.edu:your-ident): anonymous [2331 Guest login ok, send ident as password. Password: your-ident 230 Guest login ok, access restrictions apply. ftp> cd pub/neuroprose 250 CWD command successful. ftp> binary 200 Type set to I. ftp> get plutowski.active.ps.Z 200 PORT command successful. 150 Opening BINARY mode data connection for plutowski.active.ps.Z (348443 bytes). 226 Transfer complete. local: plutowski.active.ps.Z remote: plutowski.active.ps.Z 348443 bytes received in 44 seconds (7.2 Kbytes/s) ftp> quit % uncompress plutowski.active.ps.Z % lpr -P<printer-name> plutowski.active.ps b) via postal mail: Requests for hardcopies may be sent to: Kay Hutcheson CSE Department, 0114 UCSD La Jolla, CA 92093-0114 and enclose a check for $5.00 payable to "UC Regents." The report number is: Technical Report No. CS91-180 ------------------------------ Subject: New TR Available From: Bill Hart <whart@cs.UCSD.EDU> Date: Tue, 19 Feb 91 22:26:06 -0800 [[ Editor's Note: Again, please note the request of US$5.00 for "hard copy" of this paper. -PM ]] The following TR has been placed in the neuroprose archives at Ohio State University. --Bill =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-= UCSD CSE Technical Report No. CS91-180 Active selection of training examples for network learning in noiseless environments. Mark Plutowski Department of Computer Science and Engineering, UCSD, and Halbert White Institute for Neural Computation and Department of Economics, UCSD. Abstract: We derive a method for {\sl actively selecting} examples to be used in estimating an unknown mapping with a multilayer feedforward network architecture. Active selection chooses from among a set of available examples an example which, when added to the previous set of training examples and learned, maximizes the decrement of network error over the input space. New examples are chosen according to network performance on previous training examples. In practice, this amounts to incrementally growing the training set as necessary to achieve the desired level of accuracy. The objective is to minimize the data requirement of learning. Towards this end, we choose a general criterion for selecting training examples that works well in conjunction with the criterion used for learning, here, least squares. Examples are chosen to minimize Integrated Mean Square Error (IMSE). IMSE embodies the effects of bias (misspecification of the network model) and variance (sampling variation due to noise). We consider a special case of IMSE, Integrated Squared Bias, (ISB) to derive a selection criterion ($\Delta ISB$) which we maximize to select new training examples. $\Delta ISB$ is applicable whenever sampling variation due to noise can be ignored. We conclude with graphical illustrations of the method, and demonstrate its use during network training. =-=-=-=-=-=-=-=-=-=-=-=-= How to obtain a copy -=-=-=-=-=-=-=-=-=-=-=-=-=-= a) via FTP: To obtain a copy from Neuroprose, either use the "getps" program, or ftp the file as follows: % ftp cheops.cis.ohio-state.edu Connected to cheops.cis.ohio-state.edu. 220 cheops.cis.ohio-state.edu FTP server (Version 5.49 Tue May 9 14:01:04 EDT 1989) ready. Name (cheops.cis.ohio-state.edu:your-ident): anonymous [2331 Guest login ok, send ident as password. Password: your-ident 230 Guest login ok, access restrictions apply. ftp> cd pub/neuroprose 250 CWD command successful. ftp> binary 200 Type set to I. ftp> get plutowski.active.ps.Z 200 PORT command successful. 150 Opening BINARY mode data connection for plutowski.active.ps.Z (325222 bytes). 226 Transfer complete. local: plutowski.active.ps.Z remote: plutowski.active.ps.Z 325222 bytes received in 44 seconds (7.2 Kbytes/s) ftp> quit % uncompress plutowski.active.ps.Z % lpr -P<printer-name> plutowski.active.ps b) via postal mail: Requests for hardcopies may be sent to: Kay Hutcheson CSE Department, 0114 UCSD La Jolla, CA 92093-0114 and enclose a check for $5.00 payable to "UC Regents." The report number is: Technical Report No. CS91-180 ------------------------------ Subject: Manuscript available on BackPercolation From: mgj@cup.portal.com Date: Wed, 20 Feb 91 00:36:28 -0800 [[ Editor's Note: Perhaps some reader interested in the formal aspects of this paper will help the author in constructing the proper mathematical analyses of the algorithm. Any takers? Please note the request for US$10.00 to cover printing and mailing cost. -PM ]] New Manuscript Available BACKPERCOLATION : Assigning Localized Activation Error in Feedforward Perceptron Networks Mark Jurik Jurik Research & Consulting PO 2379, Aptos, Calif. USA Abstract This work introduces a new algorithm, BackPercolation, for training multilayered feedforward perceptron networks. It assigns each processing element (PE) its own activation error, thereby giving each PE its own error surface. In contrast, Backpropagation decreases global error by descending along gradients of the global error surface. Experimental results reveal that weight adjustments which reduce local activation errors permit the system to "tunnel through" the global error surface, increasing convergence rate and the likelihood of attaining an optimal minima. **************** In early 1990, over 30 researchers had experimented with a preliminary version of Backpercolation (Perc). Their feedback motivated the development of a more sophisticated version that includes the following options: learn rate feedback control and a "kick-starter" for weight initialization. Although Perc uses the gradient information that is backpropagated through a multilayered network, Perc does not adjust weights in proportion to -dE/dw, where E is the global output error. This enables Perc to train networks with numerous hidden layers and still avoid the instability associated with the large dynamic variance in the gradients. Note the performance in the 6-6-6-1 (two hidden layer) configuration in the table below. Perc uses local computations that are slightly more complex than Backprop- agation, and does NOT employ any of the following techniques: - momentum, - matrix inversion or pseudo-inversion (computationally non-local), - nested subroutines (such as LineSearch), - architecture reconfiguration (troublesome with non-stationary modeling). Yet despite these simplifying constraints, Perc trains very quickly. For example, it solves the 12-2-12 encoder problem in less than 600 epochs and the 6-6-6-1 parity problem in only 93 epochs. The table below compares Perc's speed against other high-performance nets on some popular simple tests. For each test, the opposing paradigm listed is the one that the literature (listed below) revealed to be the fastest one for that test. This way, Perc is being compared to the best of the best (or something like that). The "D" symbol in the configuration column below denotes that both Perc and the compared paradigm included direct connections between the input and output nodes. The "G" symbol denotes that the hidden layer cells in both Perc and the other paradigm used Gaussian rather than sigmoidal thresholding. The Epoch Count is the number of training cycles required to get the output of every cell, for every pattern, to be within the error tolerance as specified in the respective published sources. Perc's epoch count was averaged over 50 trials per problem task. Only successfully converging episodes were included in the average, but as shown below, Perc's probability of success was frequently 100%. Also keep in mind that many published articles do not mention the probability of success of convergence. (I wonder why?) ***************************************************************************** PROBLEM ERROR COMPARING PARADIGM'S PERC'S PERC'S TYPE CONFIG TOLER. PARADIGM EPOCHS EPOCHS % SUCC ------------------------------------------------------------------------- Parity 2-2-1 O.1 CONJUGATE GRADIENT 73 8 100 3-3-1 0.1 GRAM-SCHMIDT 247 18 100 2-1-1 (D) 0.1 CASCADE-CORR (D,G) 24 8 100 3-1-1 (D) 0.1 CASCADE-CORR (D,G) 32 6 100 4-4-1 (D,G) 0.1 CASCADE-CORR (D,G) 66 5 100 8-8-1 (D,G) 0.1 CASCADE-CORR (D,G) 357 28 100 6-6-6-1 * SOLIS/WETS OPTIMIZE 5713 93 80 Encoder/ 8-2-8 0.4 QUICKPROP 103 88 100 8-2-8 0.1 ** 194 100 decoder 8-3-8 0.4 QUICKPROP 22 22 100 8-3-8 0.1 CONJUGATE GRADIENT 68 28 100 10-5-10 0.4 QUICKPROP 14 15 100 10-5-10 0.1 CONJUGATE GRADIENT 71 19 100 12-2-12 0.4 ** 581 100 Linear Channel 10-10-10 0.1 SUPER-SAB 125 8 100 Multiplex 6-6-1 0.1 DELTA-BAR-DELTA 137 24 100 Symmetry 6-2-1 0.3 GAIN BACK-PROP 198 124 84 * In the 6-6-6-1 task, training stopped when the squared error, summed across all 64 training patterns, totaled less than 0.0002. ** I am unaware of any published result for this test. Data for the above comparisons were obtained from the following publications: Gain Backprop --- J. Complex Systems, Feb 1990, p 51 Delta_bar_delta --- J. Neural Networks, #4, 1988, p 295 Quickprop --- Proceedings 1988 Connectionist Models, p 38 Super-SAB --- J. Neural Networks, #5, 1990, p 561 Conjugate Gradient --- Advances in Neural Info Proc Sys 1, 1988, p 40 Cascade Correlation --- Advances in Neural Info Proc Sys 2, 1989, p 524 Gram_Schmidt --- Neural Computation, #1, 1990, p 116 Solis/Wets Optimization --- J. Neural Networks, #5, 1989, p367 As an option, the learn-rate parameter can be initially set to zero and it will automatically adjust as learning proceeds. This option frees the user from needing to find the optimal learn-rate; however, it has one major drawback: the algorithm needs to access information on all the cells, which is a non-local process. With Perc, the user is still required to determine these things: 1. number of hidden layers, 2. number of cells per hidden layer, 3. the scale of the bounds on the initialized weights. Journal reviewers of an earlier manuscript on Perc have asked for a mathematical analysis of the algorithm s stability and convergence properties. Unfortunately, I am not aware of any proper set of analytical tools for this kind of nonlinear behavior. As I see it, the literature all too frequently applies linear analysis techniques that require too many simplifying assumptions about the network. As a result, many conclusions thought to be gospel one year get discarded the next. Thus for the sake of keeping things clean, this manuscript will simply present the Perc algorithm, some derivation and lots of experimental results. You will need to verify Perc's utility for your own particular task(s). Speaking of validation, Perc has recently been licensed for inclusion into BrainCel, a commercially available set of macros which give the Excel spreadsheet program on the PC the capability to train a neural net on spreadsheet data. I have been informed that Perc has trained a neural net to predict the commodities price of leather, as well as estimate from proprietary demographic data the likelihood that a prospective customer will agree to buy a luxury cruise from a salseman over the phone. Now a computer can prepare a list of likely prospects to teleoperators and thereby cut down on useless calls that only end up irritating many people. The spreadsheet- neuralnet process of BrainCel is so automatic that the user does not even need to know what a neural network is. Call 203-562-7335 for details. A revised manuscript on BACKPERCOLATION is now available. It will include a hardcopy of the source code used to solve the 12-2-12 encoder/decoder problem. You will have enough documentation to code your own version. For one copy, please enclose US$10 (or foreign currency equivalent) to cover printing, shipping and handling expenses. Sorry, this will not be available via ftp. PS. All researchers who have tested Perc and helped develop its upgrade during this past year will automatically be receiving a free copy of the manuscript and source code. --------------------------------------------------------------- JURIK RESEARCH & CONSULTING PO BOX 2379 APTOS, CALIFORNIA 95001 --------------------------------------------------------------- ------------------------------ Subject: AI*IA Call for papers From: CHELLA%IPACRES.BITNET@ICNUCEVM.CNUCE.CNR.IT Date: Thu, 07 Feb 91 14:39:00 +0000 ******************************************************************************* * * * C A L L F O R P A P E R S * * * * A I * I A * * * * * * S E C O N D S C I E N T I F I C C O N G R E S S * * * * A N D I N D U S T R I A L E X H I B I T I O N * * * ******************************************************************************* Scientific subjects - Architectures, languages and environments - Knowledge representation and automated reasoning - Problem solving and planning - Knowledge acquisition and automatic learning - Cognitive models - Natural language - Perception and robotics - Industrial applications of artificial intelligence Call for Papers AI*IA (Italian Association for Artificial Intelligence) has been founded in 1988 with the intent of promoting the development of study and research in artificial intelligence and its applications. To this end, among a variety of activities, AI*IA organizes a National Congress every other year. The first AI*IA Congress took place in Trento in November 1989 and resulted in the presentation of more than 40 scientific papers, the exhibition of a number of industrial systems and products of AI and the presence of over 350 partecipants. The second Congress, open to international partecipation, will be held in Palermo and will focus on high quality scientific and technical results as well as on innovative industrial applications. Special sessions on Industrial Experiences are envisaged. During these sessions companies operating in the AI field will have an opportunity to illustrate their activities and to share their experiences. Papers Papers (5000 words max) must be in English. Authors must send 4 copies including summary (about 200 words) and key words, and they should point out the scientific topic being treated. Papers must treat original research and results or innovative industrial applications and must not have been previously published. Accepted papers shall be published in a special volume of "Lecture Notes in Artificial Intelligence", Springer Verlag ed. Italian and English are the Congress official languages. Deadlines Papers must arrive by April 10, 1991. Authors will receive communication of acceptance by May 31, 1991 and must send final camera-ready versions by June 30, 1991. Papers should be sent to the following address: Prof. Salvatore Gaglio CRES Centro per la Ricerca Elettronica in Sicilia Viale Regione Siciliana, 49 90046 MONREALE (Palermo) Industrial Experiences Companies interested in presenting their activities during the sessions for Industrial Experiences must make their request by May 15,1991 at the following address: Prof. Filippo Sorbello Dipartimento di Ingegneria Elettrica Viale delle Scienze - 90128 PALERMO Tel.+39-91-595735 Telefax +39-91-488452 Request should contain some documentation regarding the experiences to be presented (4 pages A4 format max) so as to evaluate pertinence with the scientific subjects of the Congress. Program Committee Chairman S. Gaglio (Universita' di Palermo) G. Berini (DIGITAL) L. Carlucci Aiello (Un. Roma La Sapienza) S. Cerri (DIDAEL) M. Del Canto (ELSAG) G. Ferrari (Universita' di Pisa) G. Guida (Universita' di Udine) F. Lauria (Universita' di Napoli) L. Lesmo (Universita' di Torino) E. Pagello (Universita' di Padova) D. Parisi (CNR) L. Saitta (Universita' di Torino) G. Semeraro (CSATA) R. Serra (DIDAEL) L. Spampinato (QUINARY) L. Stringa (IRST) P. Torasso (Universita' di Torino) R. Zaccaria (Universita' di Genova) Local Organization Lia Giangreco Ina Paladino Giusi Romano CRES Centro per la Ricerca Elettronica in Sicilia Viale Regione Siciliana, 49 90046 MONREALE (Palermo) Tel.+39-91-6406192/6406197/6404501 Telefax +39-91-6406200 Logistic Arrangements GEA Congressi S.r.l. Via C.Colombo, 24 90142 PALERMO Tel. +39-91-6373418 Telefax +39-91-6371625 Telex 910070 ADELFI Scientific Secretariat E.Ardizzone, F.Sorbello Dipartimento di Ingegneria Elettrica Universita' di Palermo Viale delle Scienze 90128 PALERMO Tel. +39-91-595735/489856/421639 Telefax +39-91-488452 ------------------------------ End of Neuron Digest [Volume 7 Issue 10] ****************************************